IGBT modules promise higher drive efficiencies

Even more efficient variable speed drives could soon emerge following the development of a new IGBT (integrated gate bipolar transistor) module by the power semiconductor specialist, Semikron. The company says that its Semix half-bridge modules, currently being evaluated by several drives manufacturers, could cut conduction loses by up to 40%, compared to rival products.

The modules are designed to exploit the low saturation voltages of "trench" IGBTs to harness their full potential. They can be used to create inverters using either a standard six-pack approach, or three separate, thermally decoupled half-bridges in the same package. The half-bridges cut thermal resistance by about 20%, increasing the current rating by 15% - or reducing the chip temperature by 10-15%, thus extending its life.

"People have been waiting for the half-bridge approach," says Dr Thomas Stockmeier, Semikron`s chief technology officer. He reports that initial feedback from the drive manufacturers is that the improved performance "is really there". He expects the first drives using the new devices to emerge during 2004.

The modules cover ratings from 190-1,000A in three sizes.

The global IGBT module market is worth around $500m and is growing by 9.2% a year. Semikron is the European market leader, with about 34% of the power module market.

• Semikron has reached an agreement with Chorus Motors to design and manufacture integrated power assemblies for Chorus` Meshcon multi-phase motor and drive. The deal gives Semikron exclusive supplier status for certain markets. "We are expecting Chorus Meshcon to lead to considerable new business for Semikron," says the company`s managing director, Parl Newman. Chorus has recently been granted a US patent covering its motor-drive system which delivers high torque at low speeds, while providing sufficient voltage for high-speed applications.